A number of radio communication modes are known. Simple two-way radio communications primarily use a simplex synchronous channel. This means that a single channel (frequency) is used, and a user can either send (speak) or receive (hear), but not both at the same time. In either case, whether the user is acting as a sender or a receiver, the sending and receiving of the signal occurred substantially simultaneously at both ends of the channel. Hence the communication is said to be synchronous. Common embodiments of such two-way synchronous radios are typically operated by depressing the “talk” button on the microphone. Of course, if both users depress their talk buttons at the same, then neither user hears anything.
A more modern version of such a two-way radio uses a duplex synchronous channel. In this case, both users can send and receive at the same time, and each user hears the other user's words as they are spoken. The most common form of this type of radio is the ubiquitous cellular telephone.
A characteristic of synchronous communication devices is that both the transmitter and receiver must be connected to the channel for the entire time that the communications occur. This is a problem in heavily populated urban areas where the number of available channels is much smaller than the number of potential users. In addition, cellular telephones requires a large number of buttons, and a display. This makes it difficult and distracting to operate the device. In addition, many users may desire to receive communications only at times selected by them, not at the times selected by senders.
Another problem with voice operated devices is to correctly recognize numbers, such as spoken telephone numbers, especially in the case that the identifier is in the form of large sequence of numbers, such as a security code or an account code much may well run twenty digits long.
One-way asynchronous communications devices have been available in the form of pagers. Typically, such devices can only passively receive and display simple textual messages such as telephone numbers of calling numbers. In most cases, a service provider is required to connect the pagers to standard telephone networks.
U.S. Pat. No. 4,860,359 issued to Eicher on Aug. 22, 1989 “Method of voice operated transmit control,” described a voice activated audio transmission system. There, an input signal was compared with an anti-VOX signal. As soon as a voice was detected, the voice signal was coupled for synchronous transmission.
U.S. Pat. No. 5,008,954 issued to Oppendahl on Apr. 16, 1991 “Voice-activated radio transceiver,” described a voice-activated transceiver that provided audio tones through earphones of the transceiver to announce the transition to and from transmit mode. By listening for the tones, the user was continuously apprised of the status of the transceiver.
U.S. Pat. No. 5,042,063 issued Sakanishi, et al. on Aug. 20, 1991 “Telephone apparatus with voice activated dialing function,” described a telephone in which a call could be placed by either dialing or speaking telephone numbers.
U.S. Pat. No. 5,584,052 issued to Gulau, et al. on Dec. 10, 1996 “Integrated microphone/pushbutton housing for voice activated cellular phone,” described a voice controlled vehicle accessory system responsive to voice commands and manual commands. Manual commands were entered via a single pushbutton having multiple functions depending upon an instantaneous state of a system controller. Predetermined voice commands were entered via a microphone. The types of accessories that could be coupled to the controller included the car throttle, audio system, climate system, and a cellular telephone.
U.S. Pat. No. 6,010,216 issued to Jesiek on Jan. 4, 2000 “‘Hear speak’ two way voice radio communications eyeglasses,” described a radio transceiver incorporated into eyeglasses. The transceiver included a voice activated switch to switch between receive and transmit mode.
U.S. Pat. No. 6,212,408 issued to Son, et al. on Apr. 3, 2001 “Voice command system and method,” described a system that allowed a communication device to accept voice commands from a user. The voice commands included commands to execute or dial key sequences or commands to control device functionality. Voice commands were received from a user of the communication device, indicating a command to be carried out by said communication device. Manual entry could be requested by the user in response to button activity or by a spoken command.
U.S. Pat. No. 6,236,969 issued to Ruppert, et al. on May 22, 2001 “Wearable telecommunications apparatus with voice/speech control features,” described a wearable communication apparatus in the form of a self-contained telephone headset. The headset could be activated by rotation of the mouthpiece into an operative position and deactivated by rotation out of that position. The base could be connected to a telephone network via a traditional landline, and communicate with the headset via an RF antenna. The headset included voice recognition capabilities that allowed the user to dial telephone numbers, access a memory of stored numbers, and direct certain headset functions simply by spoken commands.
Therefore, there is a need to provide two-way asynchronous data communications in a portable device that can be entirely controlled by spoken commands and identification phrases.